2. Description of Prior Art
On an average, 26 million Americans, out of which 70% are women, suffer from migraine. Migraine headaches are a recurrent, throbbing headache generally felt on one side of the head, which usually begins in early childhood or in adolescent life. Migraines are caused by rapid dilation and constriction of blood vessels in the brain. This leads to increased pressure on the pain fibers in the blood vessel wall leading to severe headache. The most common triggering factors of migraine are hunger, extreme changes in weather, fatigue, emotional stress and oral contraceptives.
Although there are various factors that trigger migraine in any particular patient, researchers and physicians believe that migraine is finally a neurobiological disorder involving one or more overlapping neurobiological mechanisms. The pathophysiology of migraine involves both the Central Nervous System (CNS) and peripheral pathways. The peripheral pathways involve blood vessels and the CNS pathways involve the cortex, raphae nuclei and trigeminal caudate nucleus. It is observed that migraine headaches begin in the cortex region of the brain with possible changes in electrical activity. This descends to the brain stem region, which has maximum serotonergic projections. Trigeminal caudate nucleus, which is a brain stem region, is an important center for headaches and is affected in migraine headache. The activation of trigeminal sensory nerve fibers leads to a painful neurogenic inflammation within the meningeal vasculature. This results in the release of neuropeptides from trigeminal sensory fibers characterized by vasodilatation and plasma protein extravasation. Thus, although alterations in blood vessels are manifested as the final common pathway, a cascade of events initiating from cortex and affecting various structures, involving different pathways and release of neurotransmitters are seen in the brain.
The level of serotonin in the blood alters at the onset of headache and is normal between migraine attacks. Serotonin is a neurotransmitter present in the central nervous system and is normally inhibitory in function. It suppresses nerve signals in neurons and is commonly known as 5-HT (5-Hydroxytryptan). Migraine can be precipitated by the drug reserpine, which depletes serotonin and is relieved by serotonin agonists that combine with the receptors and simulate serotonin activity. In the vascular tissue, it is known that sumatriptan and other triptan drugs cause constriction of blood vessels in the cerebral region and reverses neurogenic inflammation around blood vessels during migraine attacks.
In spite of considerable research into causes and treatment of migraine, cure for this disease has eluded scientists. Among the various medications that are available the family of drugs called triptans are the most effective. The basic mode of action of all these triptan drugs is known to involve selective activation of certain serotonin receptor subtypes, primarily 5HT-1B receptors present on blood vessels and 5HT-1D receptors which are seen on the nerve cell terminals in both peripheral and central nervous system. Triptans are known to relieve migraine headache by constricting the swollen cranial blood vessels and thereby reducing pain. However, it is known that the blood-brain barrier opens during migraine allowing the triptans to enter the brain and thereby exposing the neurons to adverse reactions.
Though triptans are widely used for migraine, they do not work well for all patients. It is known that triptans do not work well in 20–25% of the patients and fail 40% of the time in patients who have earlier responded well to this class of drugs. The other disadvantages of present medication prescribed for migraine headaches are:                1) Simple analgesics used for headache cannot cure migraine in particular. Addiction to these medicines can lead to gastric ulcers        2) Repeated triptan intake leads to recurrent and chronic headaches        3) Triptan drugs have major side effects like cardiovascular problems, hypertension and even stroke.        4) Other common side effects are head, jaw, chest and arm discomfort and their tightening or tingling. Throat discomfort, muscle cramps and flushing are also seen.        
The drawbacks in the treatment, and deficiencies in understanding Migraine has also been shown in U.S. Pat. No. 6,068,999. And, considering the number of people suffering from this disease there is an urgent need for a safe and effective treatment for migraine.
Alzheimer's disease is one of the most complex and perplexing neurodegenerative diseases characterized by memory loss, deterioration of language skills, impaired visuospatial skills, poor judgment, indifferent attitude, but preserved motor function. Basal forebrain and cholinergic systems are the principal targets in this disease. Patients suffer from a progressive performance degradation of visual recognition and memory.
No cure for Alzheimer's disease is currently available and no treatment can stop its advancement. In the early and middle stages of the disease drugs like tacrine, donepezil, rivastigmine, etc may help to prevent the symptoms from aggravating for a limited period of time. All these drugs have side effects. Tacrine may cause nausea, vomiting, diarrhea, abdominal pain, skin rash and can also damage the liver. Donepezil's side effects include nausea, vomiting, diarrhea, insomnia and anorexia.
Present day therapies focus on treating the associated symptoms like depression, agitation, sleep disorders, hallucinations and delusions. Addition of precursors like choline, lecithin and muscuranic agonists have proved ineffective. Alzheimer's disease is being actively researched. A number of new drugs are being tested to see if they prevent or slow the disease.
Parkinson's disease is another common neurodegenerative disease found in the elderly population. About 50,000 new cases of this disease are reported in USA alone. Major clinical manifestations of this disease are bradekinesia (difficulty in voluntary movements), rigidity, body tremors, postural instability and impaired balance. This disease is marked by loss of pigmented neurons in the substantia nigra in the mid brain region. Dopamine neurons in the substantia nigra and other catecholamine neurons in the brainstem are selectively lost in this condition. The cause of cell death or impairment is not known.
Parkinson's disease cannot be cured at present. Medication is available to provide relief from the symptoms. There are two general approaches to the treatment of Parkinson's disease with medication. The first approach attempts to slow the loss of dopamine in the brain and the second approach attempts to treat the symptoms of Parkinson's disease by other means. Dopamine agonists do carry a higher risk of short-term side effects such as nausea, vomiting, dizziness, light-headedness, confusion, and hallucinations. Anticholinergics are used to restore the balance between the two brain neurotransmitters dopamine and acetylcholine, by reducing the amount of acetylcholine. This reduces tremor and muscle stiffness in patients with Parkinson's. These medications, however, can impair memory and thinking, especially in older people; therefore, they are rarely used today.
Levadopa is the most widely used drug for Parkinson's disease though not all symptoms respond to it. It delays the onset of debilitating symptoms for some time. Levadopa is not without side effects. Nausea, vomiting, low blood pressure, involuntary movements and restlessness are seen in patients using this medication.
Trigeminal neuralgia affects the trigeminal nerve in the head. This nerve is responsible for sending impulses of touch, pain, pressure and temperature to the brain from the face. Though not fatal this disease is characterized by sudden stabbing pain felt on one side of the face. Another feature of this disorder is successive recurrences and remissions that may incapacitate the patient. Treatment for this condition includes anticonvulsant medicines such as carbamazepine or phenytoin. If this fails, surgical intervention is recommended.
Glaucoma is a major public health problem affecting about sixty six million people around the world. There are approximately three million patients in America alone. Glaucoma is an optic nerve degenerative disease that causes loss of vision and blindness. A characteristic feature of glaucoma is the progressive death of retinal ganglion cells. In many cases this is caused by the increased intraocular pressure, which leads to axonal degeneration in the optic nerve and loss of ganglion cells.
Early diagnosis is very important in the treatment of glaucoma. Though there is no cure to this disease it can be controlled to some extent with surgery and medication. Prolonged usage of drugs is required. Some medicines can cause headaches or have side effects on other parts of the body. There is an urgent need for new medicines that specifically arrest ganglion cell death.
As has been described above, diseases of the brain are generally incurable. All available treatments are symptomatic and relief is limited. Prolonged usage of drugs has variety adverse effects on the patients. Treatment often calls for surgical intervention. Invasive procedures are not free of risks. They have the potential to cause irreversible damage. U.S. Pat. No. 6,405,079 while discussing the various shortfalls in treating neurological and other problems, offers yet another invasive procedure that may require permanent implantation of electrodes. U.S. Pat. No. 6,277,372 also suggests that there is a general lack of treatment for neurodegenerative diseases. It traces these diseases to defects in neural circuitry and offers a method of treating neurodegenerative diseases by transplanting porcine neural cells into a human subject. Such a method requires extremely advanced medical procedures and can be very expensive. And, as pointed out in that patent application, such treatment may be accompanied by administration of immunosuppressive drugs. Moreover, implantation of foreign neural matter as an accepted and safe course of treatment is debatable.
It is therefore the object of this invention to overcome the drawbacks described in the currently available treatments and provide a safe and natural composition to treat conditions affecting the neurological system.